1.1 Field of the Invention
This invention relates to digital computers, and particularly to digital computers adapted for use in a distributed data processing system comprising and sharing load among a plurality of individual digital computers.
1.2 Description of the Prior Art
Digital computers in general are well known in the prior art. Digital computers have been employed in "distributed computing networks" in which a plurality of computers are interconnected and are programmed to cooperate on an overall data processing task involving a related body of data and a related body of tasks to be performed thereon, with some computers doing some of the processing and then passing results or status information to other of the computers which perform other of the processing.
Using traditional general purpose computers in distributed computing networks has required that each computer perform a portion of the networking functions (intercommunication, coordination, priority arbitration, etc.) in addition to its direct data processing work. With such traditional computers, it has generally been necessary to interconnect them by means of their input/output buses so that each views the others as I/O devices and is thus responsible for detailed control over all transmissions to and from them.
1.3 Summary of the Invention
The computers of the present invention overcome the overhead-prone drawbacks of the prior art by providing an architecture in which additional intelligence is provided at junction points of the computer network, this intelligence being sufficient to perform the networking overhead functions. A bus is provided for data transfers between each computer's CPU and an intelligent I/O controller; another bus is provided for memory transfers; another bus is provided for interconnecting the computers; an intelligent bus controller is provided to transfer from any to any of the three buses. Flow of data and status information around the network is thus expedited, and the CPU of each computer is freed to devote its attention to direct data processing tasks. An intelligent controller is provided ahead of the video RAMs to free the CPU of detailed bitmap manipulation in support of graphic displays.
It is thus a general object of the present invention to provide improved digital computers.
It is a particular object of the present invention to provide digital computers that may be interconnected to form a highly efficient distributed computing system.
Additional objects and advantages will be apparent to one skilled in the art, after referring to the description of the preferred embodiment and the appended drawings.